Hypotension, poor cardiac reserve & heart failure. Should not be used in cardiogenic shock, recent MI, acute unstable angina. Not for treatment of angina attack in chronic stable angina. May increase risk of heart failure in patients w/ severe aortic stenosis. Exacerbation of angina in sudden w/drawal. Discontinue use in patients who experience ischaemic pain. Monitor serum-K conc. Renal artery stenosis. Renal & hepatic impairment. Lactation.